The invention relates to picture frames, especially to a clamping device which is used to reinforce and hold together the mitered corners of a metal picture frame that has a rearwardly facing slot or channel which extends longitudinally of each of the framing members of which the picture frame is made.
At present, one or more rigid, L-shaped, flat metal plates with set screws are used to reinforce and clamp together the mitered corners of adjacent picture framing members. Such plates are stamped and relatively expensive to manufacture. Further, the flatness of these plates provide limited frictional engagement with the framing members. The invention is designed to provide an improved clamping device which provides greater surface contact of the device with the framing members as well as an unusual mechanism for operating the device.